[edwr]

fwiw, I installed Windows 7 64-bit yesterday with legacy boot enabled and uefi disabled. There's also a BIOS option in one of the later menus for Windows 7, instead of 8.X. I made the USB drive using Rufus, though I doubt that makes a difference.

There are no graphics drivers for 32-bit Windows 7 yet, and 64-bit is missing USB 3.0 drivers currently, but it otherwise works fine as far as I can tell.